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The complexity of information processing in the brain requires the development of technologies that can provide spatial and temporal resolution by means of dense electrode arrays paired with high-channel-count signal acquisition electronics. In this work, we present an ultra-low noise modular 512-channel neural recording circuit that is scalable to up to 4096 simultaneously recording channels. The neural readout application-specific integrated circuit (ASIC) uses a dense 8.2 mm × 6.8 mm 2D layout to enable high-channel count, creating an ultra-light 350 mg flexible module. The module can be deployed on headstages for small animals like rodents and songbirds, and it can be integrated with a variety of electrode arrays. The chip was fabricated in a TSMC 0.18 µm 1.8 V CMOS technology and dissipates a total of 125 mW. Each DC-coupled channel features a gain and bandwidth programmable analog front-end along with 14 b analog-to-digital conversion at speeds up to 30 kS/s. Additionally, each front-end includes programmable electrode plating and electrode impedance measurement capability. We present both standalone and in vivo measurements results, demonstrating the readout of spikes and field potentials that are modulated by a sensory input.

Small extracellular vesicles (sEVs) are cell-released vesicles ranging from 30-150nm in size. They have garnered increasing attention because of their potential for both the diagnosis and treatment of disease. The diversity of sEVs derives from their biological composition and cargo content. Currently, the isolation of sEV subpopulations is primarily based on bio-physical and affinity-based approaches. Since a standardized definition for sEV subpopulations is yet to be fully established, it is important to further investigate the correlation between the biomolecular composition of sEVs and their physical properties. In this study, we employed a platform combining single-vesicle surface-enhanced Raman spectroscopy (SERS) and machine learning to examine individual sEVs isolated by size-exclusion chromatography (SEC). The biomolecular composition of each vesicle examined was reflected by its corresponding SERS spectral features (biomolecular "fingerprints"), with their roots in the composition of their collective Raman-active bonds. Origins of the SERS spectral features were validated through a comparative analysis between SERS and mass spectrometry (MS). SERS fingerprinting of individual vesicles was effective in overcoming the challenges posed by EV population averaging, allowing for the possibility of analyzing the variations in biomolecular composition between the vesicles of similar and/or different sizes. Using this approach, we uncovered that each of the size-based fractions of sEVs contained particles with predominantly similar SERS spectral features. Indeed, more than 84% of the vesicles residing within a particular group were clearly distinguishable from that of the other EV sub-populations, despite some spectral variations within each sub-population. Our results suggest the possibility that size-based EV fractionation methods produce samples where similarly eluted sEVs are correlated with their respective biochemical contents, as reflected by their SERS spectra. Our findings therefore highlight the possibility that the biogenesis and respective biological functionalities of the various sEV fractions may be inherently different.

The Delta Smelt is a largely zooplank­tivorous, endangered fish endemic to the San Francisco Estuary (the estuary). High flows increase the availability of fresh and brackish water habitat for Delta Smelt, but also may mobilize contaminants, potentially increasing toxicological stress. Here, we examine the association between contaminants and Delta Smelt health across contrasting water year types and flow-related management actions. Our study spanned the fall season of three years: 1 dry year (2018) bracketed by 2 wet years (2017 and 2019) and coincided with several management actions meant to benefit Delta Smelt. We collected field water from six sites in the estuary that encompass the freshwater and low-salinity habitat of Delta Smelt and analyzed the water for contaminant concentrations. After a 96-hour exposure to the field water, we assessed cultured Delta Smelt survival and the histopathological condition of the gill and liver. Insecticides, particularly fipronil metabolites, were the most prevalent contaminants detected in 2017 and 2018, and a variety of contaminants associated with the rice harvest were detected in 2019. No acute toxicity was observed during any exposure, but we observed negative effects in the livers of Delta Smelt exposed to agricultural water from the Toe Drain and Cache Slough during a 2019 pulse flow action, which coincided with elevated detections and concentrations of organic pesticides. Other noteworthy sub-lethal effects, likely occurring in response to contaminant mixtures, included severe gill lesions in Delta Smelt exposed to Decker Island water in 2019. In the drier year of 2018, lesions were generally mild or absent. Thus, the trade-offs between increased habitat availability and contaminant loading may provide one explanation for why Delta Smelt abundance does not consistently respond positively to outflow.

This paper introduces an innovative approach to 3D environmental mapping through the integration of a compact, handheld sensor package with a two-stage sensor fusion pipeline. The sensor package, incorporating LiDAR, IMU, RGB, and thermal cameras, enables comprehensive and robust 3D mapping of various environments. By leveraging Simultaneous Localization and Mapping (SLAM) and thermal imaging, our solution offers good performance in conditions where global positioning is unavailable and in visually degraded environments. The sensor package runs a real-time LiDAR-Inertial SLAM algorithm, generating a dense point cloud map that accurately reconstructs the geometric features of the environment. Following the acquisition of that point cloud, we post-process these data by fusing them with images from the RGB and thermal cameras and produce a detailed, color-enriched 3D map that is useful and adaptable to different mission requirements. We demonstrated our system in a variety of scenarios, from indoor to outdoor conditions, and the results showcased the effectiveness and applicability of our sensor package and fusion pipeline. This system can be applied in a wide range of applications, ranging from autonomous navigation to smart agriculture, and has the potential to make a substantial benefit across diverse fields.

The role of gut microbe-derived metabolites in the development of metabolic syndrome (MetS) remains unclear. This study aimed to evaluate the associations of gut microbe-derived metabolites and MetS traits in the cross-sectional Metabolic Syndrome In Men (METSIM) study. The sample included 10,194 randomly related men (age 57.65 ± 7.12 years) from Eastern Finland. Levels of 35 metabolites were tested for associations with 13 MetS traits using lasso and stepwise regression. Significant associations were observed between multiple MetS traits and 32 metabolites, three of which exhibited particularly robust associations. N-acetyltryptophan was positively associated with Homeostatic Model Assessment for Insulin Resistant (HOMA-IR) (β = 0.02, p = 0.033), body mass index (BMI) (β = 0.025, p = 1.3 × 10-16), low-density lipoprotein cholesterol (LDL-C) (β = 0.034, p = 5.8 × 10-10), triglyceride (0.087, p = 1.3 × 10-16), systolic (β = 0.012, p = 2.5 × 10-6) and diastolic blood pressure (β = 0.011, p = 3.4 × 10-6). In addition, 3-(4-hydroxyphenyl) lactate yielded the strongest positive associations among all metabolites, for example, with HOMA-IR (β = 0.23, p = 4.4 × 10-33), and BMI (β = 0.097, p = 5.1 × 10-52). By comparison, 3-aminoisobutyrate was inversely associated with HOMA-IR (β = -0.19, p = 3.8 × 10-51) and triglycerides (β = -0.12, p = 5.9 × 10-36). Mendelian randomization analyses did not provide evidence that the observed associations with these three metabolites represented causal relationships. We identified significant associations between several gut microbiota-derived metabolites and MetS traits, consistent with the notion that gut microbes influence metabolic homeostasis, beyond traditional risk factors.

Alzheimer's disease (AD) is a neurodegenerative disease that commonly causes dementia. Identifying biomarkers for the early detection of AD is an emerging need, as brain dysfunction begins two decades before the onset of clinical symptoms. To this end, we reanalyzed untargeted metabolomic mass spectrometry data from 905 patients enrolled in the AD Neuroimaging Initiative (ADNI) cohort using MS-DIAL, with 1,304,633 spectra of 39,108 unique biomolecules. Metabolic profiles of 93 hydrophilic metabolites were determined. Additionally, we integrated targeted lipidomic data (4873 samples from 1524 patients) to explore candidate biomarkers for predicting progressive mild cognitive impairment (pMCI) in patients diagnosed with AD within two years using the baseline metabolome. Patients with lower ergothioneine levels had a 12% higher rate of AD progression with the significance of P = 0.012 (Wald test). Furthermore, an increase in ganglioside (GM3) and decrease in plasmalogen lipids, many of which are associated with apolipoprotein E polymorphism, were confirmed in AD patients, and the higher levels of lysophosphatidylcholine (18:1) and GM3 d18:1/20:0 showed 19% and 17% higher rates of AD progression, respectively (Wald test: P = 3.9 × 10-8 and 4.3 × 10-7). Palmitoleamide, oleamide, diacylglycerols, and ether lipids were also identified as significantly altered metabolites at baseline in patients with pMCI. The integrated analysis of metabolites and genomics data showed that combining information on metabolites and genotypes enhances the predictive performance of AD progression, suggesting that metabolomics is essential to complement genomic data. In conclusion, the reanalysis of multiomics data provides new insights to detect early development of AD pathology and to partially understand metabolic changes in age-related onset of AD.

The COVID-19 pandemic forced instructors of chemistry lab classes to develop a variety of alternative materials for remote delivery of traditional hands-on content. One solution to this challenge was virtual choose-your-own-adventure (CYOA) laboratories that allowed students to practice realistic decision-making and collect authentic data. With the return to in-person instruction, these CYOA laboratories can be modified into prelab exercises to support and supplement in-person experiments. Four virtual CYOA laboratories were adapted into prelab exercises for an upper-division instrumental analysis course to prepare students for experiments in chromatography method development and electronic circuit design. Students were surveyed to gauge their opinions on the prelabs and their comfort in the laboratory overall. Survey results indicated that students enjoyed the CYOA prelab activities and found them helpful in feeling prepared for experiments and understanding the source and quality of their experimental data. Students who completed the virtual prelabs met more learning objectives in several important categories on lab reports for two electronic circuit design experiments. Virtual CYOA prelabs may be a good way for instructors to expand the depth of their lab curriculum, improve student learning in the lab, and reduce the anxiety that their students feel before complex experiments.

Microbial competition within plant tissues affects invading pathogens' fitness. Metabolomics is a great tool for studying their biochemical interactions by identifying accumulated metabolites. Xylella fastidiosa, a Gram-negative bacterium causing Pierce's disease (PD) in grapevines, secretes various virulence factors including cell wall-degrading enzymes, adhesion proteins, and quorum-sensing molecules. These factors, along with outer membrane vesicles, contribute to its pathogenicity. Previous studies demonstrated that co-inoculating X. fastidiosa with the Paraburkholderia phytofirmans strain PsJN suppressed PD symptoms. Here, we further investigated the interaction between the phytopathogen and the endophyte by analyzing the exometabolome of wild-type X. fastidiosa and a diffusible signaling factor (DSF) mutant lacking quorum sensing, cultivated with 20% P. phytofirmans spent media. Liquid chromatography-mass spectrometry (LC-MS) and the Method for Metabolite Annotation and Gene Integration (MAGI) were used to detect and map metabolites to genomes, revealing a total of 121 metabolites, of which 25 were further investigated. These metabolites potentially relate to host adaptation, virulence, and pathogenicity. Notably, this study presents the first comprehensive profile of X. fastidiosa in the presence of a P. phytofirmans spent media. The results highlight that P. phytofirmans and the absence of functional quorum sensing affect the ratios of glutamine to glutamate (Gln:Glu) in X. fastidiosa. Additionally, two compounds with plant metabolism and growth properties, 2-aminoisobutyric acid and gibberellic acid, were downregulated when X. fastidiosa interacted with P. phytofirmans. These findings suggest that P. phytofirmans-mediated disease suppression involves modulation of the exometabolome of X. fastidiosa, impacting plant immunity.

Liquid chromatography-high-resolution mass spectrometry (LC-HRMS), as applied to untargeted metabolomics, enables the simultaneous detection of thousands of small molecules, generating complex datasets. Alignment is a crucial step in data processing pipelines, whereby LC-MS features derived from common ions are assembled into a unified matrix amenable to further analysis. Variability in the analytical factors that influence liquid chromatography separations complicates data alignment. This is prominent when aligning data acquired in different laboratories, generated using non-identical instruments, or between batches from large-scale studies. Previously, we developed metabCombiner for aligning disparately acquired LC-MS metabolomics datasets. Here, we report significant upgrades to metabCombiner that enable the stepwise alignment of multiple untargeted LC-MS metabolomics datasets, facilitating inter-laboratory reproducibility studies. To accomplish this, a "primary" feature list is used as a template for matching compounds in "target" feature lists. We demonstrate this workflow by aligning four lipidomics datasets from core laboratories generated using each institution's in-house LC-MS instrumentation and methods. We also introduce batchCombine, an application of the metabCombiner framework for aligning experiments composed of multiple batches. metabCombiner is available as an R package on Github and Bioconductor, along with a new online version implemented as an R Shiny App.

Lipids play crucial roles in many biological processes. Mapping spatial distributions and examining the metabolic dynamics of different lipid subtypes in cells and tissues are critical to better understanding their roles in aging and diseases. Commonly used imaging methods (such as mass spectrometry-based, fluorescence labeling, conventional optical imaging) can disrupt the native environment of cells/tissues, have limited spatial or spectral resolution, or cannot distinguish different lipid subtypes. Here we present a hyperspectral imaging platform that integrates a Penalized Reference Matching algorithm with Stimulated Raman Scattering (PRM-SRS) microscopy. Using this platform, we visualize and identify high density lipoprotein particles in human kidney, a high cholesterol to phosphatidylethanolamine ratio inside granule cells of mouse hippocampus, and subcellular distributions of sphingosine and cardiolipin in human brain. Our PRM-SRS displays unique advantages of enhanced chemical specificity, subcellular resolution, and fast data processing in distinguishing lipid subtypes in different organs and species.

Fluorescence microscopy can provide valuable information about cell interior dynamics. Particularly, mean squared displacement (MSD) analysis is widely used to characterize proteins and sub-cellular structures' mobility providing the laws of molecular diffusion. The MSD curve is traditionally extracted from individual trajectories recorded by single-particle tracking-based techniques. More recently, image correlation methods like iMSD have been shown capable of providing averaged dynamic information directly from images, without the need for isolation and localization of individual particles. iMSD is a powerful technique that has been successfully applied to many different biological problems, over a wide spatial and temporal scales. The aim of this work is to review and compare these two well-established methodologies and their performance in different situations, to give an insight on how to make the most out of their unique characteristics. We show the analysis of the same datasets by the two methods. Regardless of the experimental differences in the input data for MSD or iMSD analysis, our results show that the two approaches can address equivalent questions for free diffusing systems. We focused on studying a range of diffusion coefficients between D = 0.001μm2s-1and D = 0.1μm2s-1, where we verified that the equivalence is maintained even for the case of isolated particles. This opens new opportunities for studying intracellular dynamics using equipment commonly available in any biophysical laboratory.

IntroductionMeta-analyses across diverse independent studies provide improved confidence in results. However, within the context of metabolomic epidemiology, meta-analysis investigations are complicated by differences in study design, data acquisition, and other factors that may impact reproducibility.ObjectiveThe objective of this study was to identify maternal blood metabolites during pregnancy (> 24 gestational weeks) related to offspring body mass index (BMI) at age two years through a meta-analysis framework.MethodsWe used adjusted linear regression summary statistics from three cohorts (total N = 1012 mother-child pairs) participating in the NIH Environmental influences on Child Health Outcomes (ECHO) Program. We applied a random-effects meta-analysis framework to regression results and adjusted by false discovery rate (FDR) using the Benjamini-Hochberg procedure.ResultsOnly 20 metabolites were detected in all three cohorts, with an additional 127 metabolites detected in two of three cohorts. Of these 147, 6 maternal metabolites were nominally associated (P  100), we failed to identify significant metabolite associations after FDR correction. Our investigation demonstrates difficulties in applying epidemiological meta-analysis to clinical metabolomics, emphasizes challenges to reproducibility, and highlights the need for standardized best practices in metabolomic epidemiology.

Inertial measurement units (IMUs) provide exciting opportunities to collect large volumes of running biomechanics data in the real world. IMU signals may, however, be affected by variation in the initial IMU placement or movement of the IMU during use. To quantify the effect that changing an IMU's location has on running data, a reference IMU was 'correctly' placed on the shank, pelvis, or sacrum of 74 participants. A second IMU was 'misplaced' 0.05 m away, simulating a 'worst-case' misplacement or movement. Participants ran over-ground while data were simultaneously recorded from the reference and misplaced IMUs. Differences were captured as root mean square errors (RMSEs) and differences in the absolute peak magnitudes and timings. RMSEs were ≤1 g and ~1 rad/s for all axes and misplacement conditions while mean differences in the peak magnitude and timing reached up to 2.45 g, 2.48 rad/s, and 9.68 ms (depending on the axis and direction of misplacement). To quantify the downstream effects of these differences, initial and terminal contact times and vertical ground reaction forces were derived from both the reference and misplaced IMU. Mean differences reached up to -10.08 ms for contact times and 95.06 N for forces. Finally, the behavior in the frequency domain revealed high coherence between the reference and misplaced IMUs (particularly at frequencies ≤~10 Hz). All differences tended to be exaggerated when data were analyzed using a wearable coordinate system instead of a segment coordinate system. Overall, these results highlight the potential errors that IMU placement and movement can introduce to running biomechanics data.

Atrazine, a human-made herbicide, is infamous for its endocrine-disrupting properties, with adverse consequences on the immune, reproductive, and nervous systems. Consequently, effective recognition of atrazine in various environments, such as water, is critically important. This work presents a precise and efficient method for detecting atrazine across various environments, utilizing a well-established electrochemical technique. A metal organic framework (MOF) ZIF-67 has been synthesized and employed as a catalyst for the electrochemical detection of the triazine herbicide atrazine. Structural, morphological, and chemical analyses were conducted to evaluate the sensing material and to elucidate the interactions between the sensor and the analyte. The ZIF-67 was then integrated on the surface of the working electrode (carbon paste electrode (CPE)) to form a ZIF-67 modified-CPE (ZIF-67/MCPE). The ZIF-67/MCPE was utilized to detect atrazine by electrochemical techniques including differential pulse voltammetry (DPV) and cyclic voltammetry (CV). The sensor demonstrated excellent sensitivity and was effective in detecting atrazine. The modified sensor demonstrated a lower limit of detection (LLOD) of 3.7 μM within a linear concentration range of 4–44 μM and exhibited a strong linear correlation efficiency of 0.97. Computational results corroborated the experimental findings, revealing that the combination of ZIF-67 with atrazine forms minor triangular structures and exhibits enhanced dynamics compared to the pristine MOF. This improvement in the crystallinity of the ZIF-67 MOF with atrazine is attributed to the negative binding energy and reduced energy gap at the interface between the MOF and atrazine. Additionally, the sensor's practical application was evaluated by testing it on sewage water and fresh liquid milk. The sensor demonstrated an exceptional ability to detect atrazine, with a recovery rate ranging from 96% to 99%. This approach holds promise for developing electrochemical or solid-state devices for real-time atrazine monitoring. [ABSTRACT FROM AUTHOR]

The efficient extraction of various analytes from a wide spectrum of matrices with organic solvents is still a great challenge in analytical chemistry. Especially polar and charged compounds are hard to extract in combination with neutral analytes of intermediate to low polarity. The QuEChERS method is often chosen and has been adapted not only to the analysis of food samples, but also to environmental matrices (soil, wastewater) or biota. In this study, we overcome major drawbacks of QuEChERS such as low recoveries of charged analytes and impairment of downstream analysis by high salt loads. The new extraction method, applicable to liquid and solid samples, is called SWIEET (sugar water isopropanol ethyl nitrile extraction technique). Phase separation of the otherwise miscible extraction solvents water and acetonitrile is achieved by sugaring-out instead of salting-out. Extraction efficiencies were greatly improved by adding isopropanol to the acetonitrile phase. The concentrations of the additives glucose and isopropanol, as well as temperature, were optimized by a design of experiment. Further improvement was achieved through electro- or double-extractions. For all sample types tested (surface water, wastewater treatment plant effluent, tomato, soil, and oats), recoveries and precision were higher with SWIEET than with the established QuEChERS method. From wastewater treatment plant effluent, 75% recovery on average were achieved with our SWIEET method compared to 37% with QuEChERS for a model analyte mixture with polarities of logDpH7 = − 5.7 − 3.5. Higher recoveries and lower standard deviations compared to QuEChERS were achieved especially for polar and charged analytes such as metformin. Handling proved to be easy, since there was no additional solid phase and no tedious weighing of salts. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs), an emerging nanomaterial, have shown significant promise in the materials science. This study aims to electrochemical deposited reduce carbon dots (RCDs) and pectin (PC) scaffold on the pencil graphite electrode (PGE), resulting a multifunctional electrocatalyst support (PC/RCDs/PGE) for electroloading of the nickel nanoparticles (NiNPs) to creates the NiNPs/PC/RCDs/PGE for electrooxidation of ethanol. Comprehensive surface and structural analysis and chemical identification methods were utilized for characterization of the modified electrode. Evaluation as an electrocatalyst for ethanol oxidation in 0.1 M NaOH, demonstrated that the NiNPs/PC/RCDs/PGE shows high electrocatalytic activity (Jp = 112 mA cm−2), outperforming several comparisons modified electrodes, RCDs/PGE, NiNPs/RCDs/PGE, NiNPs/PC/PGE, and NiNPs/PGE. These findings suggest that the RCDs and PC scaffold enhances the electrocatalytic activity of the NiNPs via the increasing the surface area of electrodeposited NiNPs and synergistic effect of nanocomposite components, indicating potential for significant advancements in non-platinum ethanol oxidation electrocatalysts. [Display omitted] • The RCDs were electrodeposited at PGE by electroreduction of the synthesized CDs. •The PC was electrodeposited on/in RCDs/PGE for first time to produce PC/RCDs/PGE. •The NiNPs/PC/RCDs/PGE was prepared by electroloading of NiNPs on/in PC/RCDs/PGE. •The NiNPs/PC/RCDs/PGE was used as a potent electrocatalyst for EOR in 0.1 M NaOH. •The NiNPs/PC/RCDs/PGE displayed high electrocatalytic activity toward EOR in NaOH. [ABSTRACT FROM AUTHOR]

The objective of this work was to synthesize a new catalyst x-MoO 3 /Ni 0.5 Zn 0.5 Fe 2 O 4 using the combustion reaction method and to evaluate its catalytic potential and reuse in biodiesel production from waste oil, optimizing the process through experimental design. The catalysts were characterized in terms of structure by X-ray diffraction and phase quantification by Rietveld refinement, surface area by the Brunauer-Emmett-Teller technique, experimental density by helium pycnometry, acidity tests by ammonia desorption at programmed temperature, chemical analysis by X-ray fluorescence, morphology by scanning and transmission electron microscopy, and catalytic properties. The products of the simultaneous transesterification and esterification reactions were characterized by gas chromatography and acidity index. The results indicate the formation of catalysts with surface area ranging from 1.5 to 1.7 m2/g and density ranging from 4.5 to 5.1 g/cm3, composed of major crystalline phases of MoO 3 in the orthorhombic configuration and cubic Ni 0.5 Zn 0.5 Fe 2 O 4 ferrite, with total acidity ranging from 70 to 182 μmol/g of NH 3. Morphological characterization revealed that the catalyst comprises irregular plates of various sizes and shapes with a wide range of cluster sizes. In the simultaneous transesterification and esterification reactions of residual oil, the catalysts were active under all conditions tested, with emphasis on the catalyst containing 50 % Mo ions and 50 % Ni 0.5 Zn 0.5 Fe 2 O4 presenting the best catalytic performance with a conversion of 95 % in ethyl esters and a reduction of 71 % in acidity, with a service life of 6 cycles, an average conversion of 90 % and good thermal and structural stability after use. The experimental design was significant and predictive, with a confidence level of 95 %. Statistical analysis identified that all input variables (temperature, time, and amount of catalyst) were significant for the adopted design. The new catalyst composed of molybdenum, iron, nickel, and zinc has a positive impact on biodiesel synthesis from frying oil and ethanol. [ABSTRACT FROM AUTHOR]

Background: Protein instability has been reported to be an important cause of haze in white wines; to investigate the feasibility of protease as a substitute for bentonite in the protein stability of white grape liqueurs, the effect of protease combined with heat treatment on the composition and protein stability of liqueur wines was investigated by chemical analysis, sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE), and amino acid analysis. Results: The results showed that the contents of total acid, volatile acid, pH, and glycerol were not significantly different from the blank control; the effect on total protein content and thermal stability were similar to the bentonite treatment; the L∗, b∗, and Cab∗ values of liqueur wines increased by 5.59%, 4.33%, and 4.33% after protease combined with heat treatment (p < 0.05); SDS‐PAGE results confirmed that protease combined with heat treatment had good hydrolysis for thaumatin‐like proteins (TLPs) and chitinases (CHIs) in liqueur wines. Amino acid analysis revealed that the levels of threonine, serine, tyrosine, arginine, and proline had increased, respectively, and isoleucine (1.26 mg/L) and leucine (1.16 mg/L) were newly detected after protease combined with heat treatment. Particle size analysis showed that the protease combined with heat treatment had less effect on the particle size distribution of the wines. Conclusion: Protease combined with heat treatment had a certain protein stabilizing effect and had no significant negative impact on other nutrients of liqueur wines. Thus, it can be used as an alternative to bentonite for the protein stabilization of liqueur wines. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusions The aim of this work was to investigate the solubility and co‐solubilization of fragrance raw materials (FRMs) in sodium dodecyl sulfate (SDS) and polysorbate 20 (P20) surfactant micellar systems, which can advance our knowledge of multi‐solute micellar solubilization and fragrance olfactory performance from product matrices containing the surfactants.The transfer of individual FRMs and binary FRM mixtures into micellar phases was quantified by UV–VIS differential spectroscopy and evaluated in terms of the standard Gibbs free energy change and micelle‐water partition coefficient. Co‐solubilization effects were further evaluated by the deviation ratio.Anionic SDS was found overall to be a more efficient solubilizer than nonionic P20. On an individual basis, micellar solubilization generally increased with solute lipophilicity but was additionally impacted by solute rigidity and steric effects. Micellar solubilization was favoured for more rigid structures and less favoured for FRMs that exhibited larger molecular rotation and steric hindrance. For multi‐solute systems, three co‐solubilization effects were observed: (i) inhibitive effect in which micellar partitioning of both solutes decreased, (ii) an inverse effect where partitioning of one solute increased while the other decreased and (iii) synergistic effect in which partitioning of both solutes increased. During co‐solubilization in P20 micelles, many FRMs competed for solubilization between the polyoxyethylene chains in the outer layer of the micelle, thereby resulting in an inhibitory effect for both solutes. Co‐solubilization of FRM binary mixtures in SDS micelles often resulted in a synergistic increase in micellar solubility, possibly due to micellar swelling, thereby facilitating partitioning of additional solutes into the micelle. An inverse effect in which the micellar solubility of one solute increased, while the other decreased was observed in both surfactant systems with varying degrees of partitioning depending on the composition of the FRM mixture.The results of this study provide valuable insights into the impact of FRM composition on multi‐solute partitioning behaviour and the impact of surfactant type on co‐solubilization in micellar solutions. [ABSTRACT FROM AUTHOR]

ABSTRACT Time‐of‐flight mass spectrometry (TOF MS) excels in rapid and high‐sensitivity analysis, making it a cornerstone of analytical chemistry. But as sample complexity explodes in omics studies, so does the need for higher resolving power to ensure accurate results. Traditional TOF instruments face a challenge: achieving high resolution often requires a very large instrument. To overcome this limitation, scientists developed alternative designs for TOF analyzers called multi‐pass TOF analyzers (MPT). These MPT analyzers come in two main configurations: multi‐turn (MTT) and multi‐reflecting (MRT). Drawing on the authors’ extensive experience, this review describes two decades of MPT advancements. It highlights the critical development of optimized analyzer designs, tracing the evolution towards mirror‐based MRT instruments, generally providing superior resolution and spatial acceptance compared to MTT. While the manuscript attempts to overview MTT advances, it primarily focuses on MRT technology. Additionally, the review explores the role of orthogonal accelerators and trap pulse converters, comparing their efficiency and the dynamic range limits imposed by space charge effects. By comparing various MRT configurations and commercially available instruments, the review sets out to inform and empower researchers so they can make informed decisions about MRT mass spectrometers. [ABSTRACT FROM AUTHOR]

A mechanism for carbon deposition and its impact on the reaction kinetics of Methane Dry Reforming (MDR) using Rhodium‐based catalysts is presented. By integrating Raman spectroscopy with kinetic analysis in an operando‐annular chemical reactor under strict chemical conditions, we discovered that carbon deposition on a Rh/α‐Al2O3 catalyst follows a nucleation‐growth mechanism. The dynamics of carbon aggregates at the surface is found to be ruled by the CO2/CH4 ratio and the inlet CH4 concentration. The findings elucidate the spatiotemporal development of carbon aggregates on the catalyst surface and their effects on catalytic performance. Furthermore, the proposed mechanism for carbon formation shows that the influence of CO2 on MDR kinetics is an indirect result of carbon accumulation over time frames exceeding the turnover frequency, thus reconciling conflicting reports in the literature regarding CO2′s kinetic role in MDR. [ABSTRACT FROM AUTHOR]

Background: Melaleuca species (family Myrtaceae) are characterized by their wide-ranging applications as antimicrobials and in skin-related conditions. Herein, we estimated the volatile profile and biological significance of M. rugulosa (Link) leaves for the first time supported by a dereplication protocol. Materials and methods: Volatile components were extracted using hydrodistillation (HD), supercritical fluid (SF), and headspace (HS) techniques and identified using GC/MS. The variations among the three extracts were assessed using principal component analysis and orthogonal partial least square discriminant analysis (OPLS-DA). The extracted volatiles were tested for radical scavenging activity, anti-aging, and anti-hyperpigmentation potential. Finally, disc diffusion and broth microdilution assays were implemented to explore the antibacterial capacity against Streptococcus pyogenes, Staphylococcus aureus, Clostridium perfringens, and Pseudomonas aeruginosa. Results: The yield of the SF technique (0.8%) was three times higher than HD. GC/MS analysis revealed that the oxygenated compounds are the most proponents in the three extracts being 95.93% (HD), 80.94% (HS), and 48.4% (SF). Moreover, eucalyptol (1,8-cineol) represents the major component in the HD-EO (89.60%) and HS (73.13%) volatiles, while dl-α-tocopherol (16.27%) and α-terpineol (11.89%) represent the highest percentage in SF extract. Regarding the bioactivity profile, the HD-EO and SF-extract showed antioxidant potential in terms of oxygen radical absorbance capacity, and β- carotene assays, while exerting weak activity towards DPPH. In addition, they displayed potent anti-elastase and moderate anti-collagenase activities. The HD-EO exhibited potent anti-tyrosinase activity, while the SF extract showed a moderate level compared to tested controls. OPLS-DA and dereplication studies predicted that the selective antibacterial activity of HD-EO to S. aureus was related to eucalyptol, while SF extract to C. perfringens was related to α-tocopherol. Conclusions: M. rugulosa leaves are considered a vital source of bioactive volatile components that are promoted for controlling skin aging and infection. However, further safety and clinical studies are recommended. [ABSTRACT FROM AUTHOR]

Chemical analysis aimed at identifying post‐explosion residues is critical for investigating crimes or accidents involving explosives, establishing it as a vital area of forensic chemistry. In general, only trace amounts remain in samples analyzed for this purpose, making the presence of interferents a constant concern. Therefore, understanding the materials used from collection to sample preparation is essential for this type of analysis. This study focuses on organic contaminants in collection and laboratory materials analyzed by gas chromatography/mass spectrometry (GC/MS), complementing a previous study by Mauricio et al. (2020), which addressed inorganic contaminants in materials used for similar purposes in ion chromatography (IC). No prior studies have specifically investigated the potential organic interferences introduced by various materials commonly used in forensic laboratories for sample pre‐processing, storage, and evidence collection in this context. Plastic films, bottle caps, disposable gloves, syringes, swabs, disposable cups, plastic tubes, and plastic pipettes were examined. GC/MS analyses revealed that certain materials, particularly syringe plungers, gloves, and plastic films, can interfere with the detection of post‐explosion residues from explosive emulsions and ANFO (ammonium nitrate‐fuel oil). These findings emphasize the importance of evaluating materials for potential interferences prior to sample collection and processing to minimize contamination risks. This study provides significant insights into how commonly used laboratory materials can impact forensic analysis, thereby enhancing the reliability of post‐explosion residue analysis and supporting more accurate forensic investigations. [ABSTRACT FROM AUTHOR]

AbstractWax precipitation and deposition are challenging hurdles in pipeline transportation of waxy crude oil. This study focuses on transforming SiO2, Laponite, and montmorillonite particles into hydrophobic particles through polymer grafting. Chemical structure analysis and grafting ratio calculation were performed. Through thermogravimetric analyzer (TGA) test, Laponite showed the highest grafting ratio. The effects of adding nanocomposites, TDA-2024-22, and commercial pour point depressants on the rheological behavior and wax crystallization behavior of African crude oil were compared. Addition of the nanocomposite PDA-22@SiO2 to crude oil, reduced the viscosity by 85.6% at 20 °C and the thixotropy by 60.2%. Wax crystal size decreased in the order of PDA-22@SiO2, PDA-22@Laponite, KS-10, TDA2024-22, and PDA-22@MMT. The pour point decreased by 6 °C with PDA-22@ SiO2 particles but only 3 °C with Laponite and montmorillonite composites. Spherical nanocomposites are promising flow improvers for waxy crude oil. [ABSTRACT FROM AUTHOR]

Erianin is one of the most representative bibenzyls with significant inhibitory activity against a wide range of tumor cells. However, the low erianin level in natural materials has severely inhibited its further development in health care. Our aim was to uncover the erianin biosynthetic pathway to lay the foundation for promoting its production. Firstly, we screened and obtained two Dendrobium species (Dendrobium thyrsiflorum stems with lower erianin content and D. chrysotoxum stems with higher erianin content), belonging to the same Dendrobium section (Chrysotoxae). A systematic analysis of bibenzyl structure and content in two stems revealed that gigantol might be an erianin biosynthetic intermediate, which was verified by introducing deuterium-labeled gigantol. Chemical structure analyses indicated that gigantol was modified by two kinds of enzymes (hydroxylases and O-methyltransferases), leading to erianin synthesis. Up-regulated hydroxylases and O-methyltransferases (OMTs) were screened out and were performed by molecular docking simulation experiments. We propose a rational biosynthetic pathway from gigantol to erianin, as well as relevant enzymes involved in the process. Our findings should significantly contribute to comprehensive resolution of the erianin biosynthetic pathway, promote its large-scale industrial production as well as contribute to biosynthesis studies of other bibenzyls. [ABSTRACT FROM AUTHOR]

This study analyzes the delamination behavior of adhesive joints after exposure to a saline environment for zero, one, and twelve weeks. Delamination was assessed under static and fatigue loading conditions in fracture Modes I and II, with a detailed analysis of fracture surfaces using Scanning Electron Microscopy (SEM) and Backscattered Electron (BSE) detection. The 3D images reveal significant morphological differences in fracture surfaces, showing variations in fatigue lines and the presence of impurities depending on the fracture mode. A probabilistic fatigue life analysis was performed using a Weibull regression model, showing notable changes, especially in Mode I at a high number of cycles. A chemical analysis using EDX and FTIR-ATR complemented the mechanical study, revealing an increase in sodium and chlorine concentrations with prolonged saline exposure. Oxidative degradation was also observed, with carbonyl groups increasing significantly over time, particularly in areas most exposed to the saline mist. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs), including acenaphthene, pose a significant threat to aquatic ecosystems by harming vital organisms such as benthic invertebrates. This study evaluated the impact of environmentally relevant concentrations of acenaphthene on Tubifex tubifex, focusing on sublethal acute toxicity and subchronic biomarker responses. Key biomarkers assessed included histopathological changes and the modulation of antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), and malondialdehyde (MDA). Additionally, the study examined structure–activity relationships and species sensitivity distribution (SSD). Concentrations exceeding the solubility threshold of acenaphthene (3.9 mg/L) triggered distinct, concentration-dependent behavioral responses in Tubifex tubifex, such as clumping, mucus secretion, and body wrinkling. Prolonged exposure exacerbated these behavioral dysfunctions, while subchronic exposure resulted in significant histopathological alterations, including epithelial hyperplasia, inflammation, edema, fibrosis, and degenerative changes. The edematic appearance of the body wall suggested a potential immune response to exposure. Furthermore, increased activities of CAT, SOD, and GST indicated oxidative stress in the worms. The study found a 1.5-fold increase in CAT and GST activity, a fivefold increase in SOD, and a striking 100-fold increase in MDA levels compared to controls, signifying an overwhelmed antioxidant defense system and potential cellular disruption. The SSD curve revealed hazard concentrations (HC50 and HC90), indicating that Tubifex tubifex exhibited lower sensitivity to acenaphthene compared to other taxa. In silico analysis and read-across models confirmed the potential of acenaphthene to induce significant oxidative stress upon exposure. The correlation between biomarker responses and structure–activity relationship analysis highlighted the aromatic nature of acenaphthene as a key factor in generating reactive metabolites, inhibiting antioxidant enzymes, and promoting redox cycling, ultimately contributing to adverse outcomes. These findings, coupled with behavioral responses and SSD curve inferences, underscore the importance of the solubility threshold of acenaphthene as a critical benchmark for evaluating its ecological impact in aquatic environments. [ABSTRACT FROM AUTHOR]

Arsenic, a toxic element from both anthropogenic and natural sources, reaches surface environments through atmospheric cycling and dry and wet deposition. Biomethylation volatilizes arsenic into the atmosphere and deposition cycles it back to the surface, affecting soil-plant systems. Chemical speciation of deposited arsenic is important for understanding further processing in soils and bioavailability. However, the range of atmospheric transport and source signature of arsenic species remain understudied. Here we report significant levels of methylated arsenic in precipitation, cloud water and aerosols collected under free tropospheric conditions at Pic du Midi Observatory (France) indicating long-range transport, which is crucial for atmospheric budgets. Through chemical analyses and moisture source diagnostics, we identify terrestrial and marine sources for distinct arsenic species. Estimated atmospheric deposition fluxes of methylated arsenic are similar to reported methylation rates in soils, highlighting atmospheric deposition as a significant, overlooked source of potentially bioavailable methylated arsenic species impacting plant uptake in soils. Analyses of atmospheric samples at a high-altitude site show that methylated forms of arsenic, emitted via biological processes, represent an important share of arsenic deposition. These forms are transported from both marine and terrestrial systems. [ABSTRACT FROM AUTHOR]

Orthopedic implants have faced challenges in treating bone defects due to various factors, including inadequate osseointegration, oxidative stress, bacterial infection, immunological rejection, and poor individualized treatment. These challenges profoundly affect both the results of treatment and patients' daily lives. There is great promise for the layer-by-layer (LbL) assembly method in tissue engineering. The method primarily relies on electrostatic attraction and entails the consecutive deposition of electrolyte complexes with opposite charges onto a substrate, leading to the formation of homogeneous single layers that can be quickly deposited to produce nanolayer films. LbL has attracted considerable interest as a coating technology because of its ease of production, cost-effectiveness, and capability to apply diverse biomaterial coatings without compromising the primary bio-functional properties of the substrate materials. This review will look into the fundamentals and evolution of LbL in orthopedics, provide an analysis of the chemical strategy used to prepare bone implants with LbL and introduce the application of LbL bone implants in orthopedics over recent years. Among the many potential uses of LbL, such as the implementation of sustained-release and programmed drug delivery, which in turn promotes the osseointegration and the development of new blood vessels, as well as antibacterial, antioxidant, and other similar applications. In addition, we offer a thorough examination of cell behavior and biomaterial interaction to facilitate the advancement of next-generation LbL films for tissue engineering. [ABSTRACT FROM AUTHOR]

This study successfully prepared three environmentally friendly Schiff base network (SNW) polymers, SNW‐1, SNW‐2, and SNW‐3, using melamine and aldehyde compounds as raw materials through a microwave‐assisted synthesis method. The SNW materials were applied to catalyze the copolymerization reaction of SO2 and epoxides. Through detailed analysis of the chemical structure and properties of SNW‐1, SNW‐2, and SNW‐3, their catalytic efficiency was thoroughly investigated. Three thermal degradation kinetic models, Flynn–Wall–Ozawa (FWO), Kissinger, and Coats–Redfern, were employed to calculate the kinetic parameters of the thermal degradation of poly(cyclohexene sulfite) (PCS). Potential thermal degradation mechanisms were speculated. Additionally, the Kissinger model accurately described the thermal degradation kinetics features of PCS. Based on experimental results and kinetic analysis, this paper elucidates the potential mechanism of the copolymerization reaction of SO2 and epoxides. The study indicates that microwave‐assisted synthesis exhibits convenience and high efficiency in preparing efficient catalysts, demonstrating significant potential across various application domains. [ABSTRACT FROM AUTHOR]

Developing dressing for wound dressings represents a significant challenge for the scientific community. In this study, a conductive hydrogel was synthesized to promote the wound‐healing process. This hydrogel is composed of silk fibroin (SF), reduced graphene oxide (rGO), and glycerol (G). The impact of modifying the SF:rGO ratio, and the G content (%), on the physicochemical and biological properties. The hydrogels were characterized using FT‐IR, SEM, XRD, TGA, swelling, mechanical resistance, and conductivity. The cytotoxicity of the materials and their wound‐healing capacity in human fibroblasts were also determined. Chemical analysis revealed that the gelation of SF occurs due to the formation of β sheet structures, which was confirmed by the shift from amide I to amide II. An Increase in the SF:rGO ratio favored swelling behavior, although increasing G reduced this effect. The swelling of the hydrogel followed a Fick diffusion mechanism. Furthermore, the increase in the SF:rGO ratio and the percentage G improved the conductivity of the materials. The hydrogels were found to be non‐cytotoxic to human fibroblasts, and those containing rGO exhibited superior wound healing capacity compared to the positive control cell culture medium. Therefore, SF:rGO hydrogels could be considered promising candidates for wound dressing. [ABSTRACT FROM AUTHOR]

This chapter (Sampling as Part of the Measurement Process) is a contribution to the Geostandards and Geoanalytical Research Handbook of Rock and Mineral Analysis – an online textbook that is a fully revised and updated edition of A Handbook of Silicate Rock Analysis (P. J. Potts, 1987, Blackie, Glasgow).Chapter 1 (Part 2) forms part of Section 1 of the handbook dealing with fundamentals of measurement and instrument design. The geochemical measurement process is considered to begin when the primary sample is taken from the sampling target, rather than when that sample arrives at the laboratory. This integration of sampling within the measurement procedure enables both sampling and chemical analysis to be optimised in order to achieve a measurement procedure that is fit for its intended geochemical purpose. The key metric in judging this fitness for purpose, and hence validating a measurement procedure, is the uncertainty of each measurement value. This measurement uncertainty is explained, together with methods to estimate and express it in a way that includes the contribution from sampling, with a worked example. The resultant more realistic estimates of measurement uncertainty are shown to improve the reliability of the geochemical interpretation of measurement values. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic made it difficult to obtain pharmaceutical‐grade injectable anaesthetics used in animal experiments in Japan. To address this problem, it is worth the effort to evaluate whether the use of non‐pharmaceutical‐grade sodium pentobarbital (PBNa) water solution can be an alternative one from the perspective of stability, physicochemical properties, bioavailability and so on. In this article, as a first step, we examined the stability of PBNa 5w/v% aqueous solution (PBNa 5% AS). PBNa 5% AS sample was prepared simply by dissolving non‐pharmaceutical‐grade PBNa into water and was stored at 25°C and 5°C for 15 days. Visual appearance, pH, osmolality and assay (contents of PBNa and related substances) were tested. The stability test results indicated that there was no profound change in these test items of the PBNa 5% AS under either storage condition, suggesting that the formulation was sufficiently stable in such a short term. The only observable change was an increase of an impurity under 25°C storage; however, it was at a negligible level. Moreover, as the pH of the formulation remained <10.0 throughout the storage period in both conditions, the irritant level of the pH is considered to be acceptable. Therefore, from the viewpoint of the stability and physicochemical properties, PBNa 5% AS can be an alternative injectable anaesthetic when access to pharmaceutical‐grade anaesthetics is limited, as long as used in short‐term from its preparation. [ABSTRACT FROM AUTHOR]

Colored textiles are valuable physical evidence often found at crime scenes. Analysis of the chemical structure of textiles could be used to establish a connection between fabric found at a crime scene and suspect cloths. High-performance liquid chromatography (HPLC) and mass spectroscopy coupled HPLC are traditionally used for the identification of dyes in fabric. However, these techniques are invasive and destructive. A growing body of evidence indicates that near-infrared excitation (λ = 830 nm) Raman spectroscopy (NIeRS) could be used to probe the chemical signature of such colorants. At the same time, it remains unclear whether environmental factors, such as solar light could lower the accuracy of NIeRS-based identification of dyes in textiles. In this study, we exposed cotton fabric colored with six different dyes to light and investigated the extent to which colorants fade during seven weeks using NIeRS. We found a decrease in the intensities of all vibrational bands in the acquired spectra as the time of the exposition of fabric to light increased. Nevertheless, utilization of partial least-squared discriminant analysis (PLS-DA) enabled identification of the colorants at all eight weeks. These results indicate that the effect of light exposure should be strongly considered by forensic experts upon the NIeRS-based analysis of colored fabric. [ABSTRACT FROM AUTHOR]

Atractylodis Macrocephalae Rhizoma (AMR) is a traditional Chinese medicine used for gastrointestinal diseases. With increased demand, there are more and more places of cultivation for AMR. However, the quality of AMR varies from place to place, and there is no good way to distinguish AMR from different origins at present. In this paper, we determined the content of eight chemical components including 60% ethanol extracts, essential oil, polysaccharides, atractylenolides, and atractylone, obtained the color parameters of AMR powder by colorimetry, and odor information was captured by the electronic nose, all of which were combined with machine learning to establish a rapid origin traceability method. The results of the principal component analysis of the chemical components revealed that Zhejiang AMR has a high comprehensive score and overall better quality. The Kruskal–Wallis test demonstrated that there are varying degrees of differences in chemical composition and color parameters across the different origin. However, the accuracy of the classification model is low (less than 80%), making it difficult to distinguish between different origins of AMR. The electronic nose demonstrated excellent classification performance in the traceability of AMR from different origins, with accuracy reaching more than 90% (PLS-DA: 96.88%, BPNN: 96.88%, PSO-SVM: 100%). Overall, this study clarified the quality differences of AMR among different origins, and a rapid and precise method combining machine learning was developed to trace the origin of AMR. [ABSTRACT FROM AUTHOR]

Chemical analysis adopts a calibration curve to establish the relationship between the measuring technique's response and the target analyte's standard concentration. The calibration equation is established using regression analysis to verify the response of a chemical instrument to the known properties of materials that served as standard values. An adequate calibration equation ensures the performance of these instruments. There are two kinds of calibration equations: classical equations and inverse equations. For the classical equation, the standard values are independent, and the instrument's response is dependent. The inverse equation is the opposite: the instrument's response is the independent value. For the new response value, the calculation of the new measurement by the classical equation must be transformed into a complex form to calculate the measurement values. However, the measurement values of the inverse equation could be computed directly. Different forms of calibration equations besides the linear equation could be used for the inverse calibration equation. This study used measurement data sets from two kinds of humidity sensors and nine data sets from the literature to evaluate the predictive performance of two calibration equations. Four criteria were proposed to evaluate the predictive ability of two calibration equations. The study found that the inverse calibration equation could be an effective tool for complex calibration equations in chemical analysis. The precision of the instrument's response is essential to ensure predictive performance. The inverse calibration equation could be embedded into the measurement device, and then intelligent instruments could be enhanced. [ABSTRACT FROM AUTHOR]

Hemorrhagic disease caused by grass carp reovirus (GCRV) infection is a major problem affecting the grass carp aquaculture industry. Therefore, inhibiting the spread of GCRV infection is of great economic significance. Herein, we sequenced five tissues (gill, liver, intestine, kidney, and muscle) from grass carp before and after GCRV infection using data-independent acquisition proteomic and untargeted metabolomic technologies, and quantitatively identified 10,808 proteins and 4040 metabolites. Then, we analyzed the differentially expressed proteins (DEPs) and metabolites (DEMs) before and after GCRV infection in the five tissues. Gene ontology analysis revealed that the five tissue DEPs were enriched in metabolic, including carbohydrate and lipid metabolic processes. Chemical taxonomy analysis showed that the categories of DEMs mainly included carbohydrates and lipids, such as fatty acids, glycerophospholipids, steroids, and their derivatives. Both the proteomic and the metabolomic data showed that GCRV affected the carbohydrate and lipid metabolism in the host. Shared pathway analysis was performed at both the protein and metabolic levels, showing significant enrichment of the glycolysis and pentose phosphate pathways (p < 0.001). Further analysis of glycolysis and pentose phosphate pathway inhibitors revealed that these two pathways are important for GCRV replication. As the kidney was the most affected among the five tissues, we analyzed the butanoate metabolism in the kidney, which revealed that most of the differentially expressed proteins and differently expressed metabolites in the butanoate metabolism were related to the TCA cycle. Further investigation showed that fumaric acid, an intermediate product in the TCA cycle, significantly inhibited GCRV replication in the CIK cells (p < 0.001), and that this inhibitory effect may be related to its induction of interferon system activation. The addition of fumaric acid to feed increased the survival rate of juvenile grass carp by 19.60% during GCRV infection, and protected the tissues of those infected with GCRV, making it a potential anti-GCRV feed additive. Our results provide new perspectives on GCRV pathogenesis and antiviral strategies for grass carp. [ABSTRACT FROM AUTHOR]

Wood modification has been explored in various ways to enhance dimensional stability and reduce flammability, with a focus on environmentally friendly treatments to meet market demands. This study aimed to investigate the efficacy of new, potential fire-retardant materials. Specifically, the study examined the combination of tripotassium citrate (TPC), a water-soluble and bio-based fire retardant, with sorbitol and citric acid (SorCA), an eco-friendly thermosetting resin previously studied. While TPC is known to control combustion, its application in wood modification has not been thoroughly researched. To assess the fixation and flammability of these fire retardants, tests were conducted on Scots Pine (Pinus sylvestris L.), including chemical analysis, dimensional stability, mechanical properties, flame retardancy, and leaching tests. The combination of SorCA and TPC showed high weight percent gain (WPG) values; however, leaching and anti-swelling efficiency (ASE) tests revealed challenges in fixation stability. The dynamic mechanical properties were reduced, whereas the static strength values were in the same range compared with untreated wood. While TPC exhibited high flame retardancy prior to leaching, its efficacy diminished post-leaching, underscoring challenges in fixation and the need for improved retention strategies. Bunsen burner tests conducted on leached specimens indicated enhanced performance even under severe leaching conditions as per the EN 84:2020 procedure. However, cone calorimetry measurements showed less favorable outcomes, emphasizing the necessity for further investigation into optimizing TPC retention and enhancing treatment efficacy. [ABSTRACT FROM AUTHOR]

Ever since its invention, mass spectrometry has been seen as a remedy for all of the riddle that an analytical chemist was ever called to answer. Indeed, a good mass expert, provided with a good instrument and an updated library, would be able to answer to the question "what is it?" or "what does it have inside?". In most of the cases, nevertheless, there is sometimes the need of using other type of techniques in order to avoid misunderstandings and wrong interpretations of the results. Therefore, the aim of this work is to compare real forensic cases where mass spectrometry played a fundamental role to obtain tangible and trustable answers, to other ones where this technique proved to be totally misleading. Those that will be shown, are real, concrete cases – slightly modified in order to make them unrecognisable. [ABSTRACT FROM AUTHOR]

The neutralization of acidic solutions containing U (IV) and Ce (III) at room temperature in glove box atmosphere and in the presence of dithionite results in coprecipitation of these elements as amorphous solid solutions CexU1–xO2±y. The solubilities of the precipitates with different mole fractions (x) of Ce(OH)3 (x = 0.01 or 0.1) were determined in 1 M NaClO4 solutions between pH 2.2 and 12.8 under reducing conditions. The solids were investigated by a variety of methods (chemical analysis, SEM‐EDX, XRD, XPS, XAS) to determine the nature of the solid solutions formed, their composition and the valence state of Ce and U. X‐ray photoelectron spectroscopy confirmed the oxidation states of the solids both before and after the equilibration as Ce (III) and U (IV). The amorphous coprecipitates reached equilibrium relatively fast (∼1 week). The release of Ce from the coprecipitates was totally dominated by the release of uranium over the whole pH range. The Ce concentrations decrease slightly with the decrease of Ce content in the solid, suggesting that CexU1–xO2±y solids behave thermodynamically as solid solutions. The concentrations of U in equilibrium with the coprecipitate were in excellent agreement with the solubility of UO2(s) under reducing conditions reported in the literature. The conditional solubility product of Ce(OH)3 from the coprecipitate was several orders of magnitude (∼4 in the near neutral pH range and ∼18 in the acidic range) lower than that of pure Ce(OH)3(s). The activities and activity coefficients of Ce(OH)3(s) in the coprecipitate were also estimated. Activity coefficients are much less than 1, indicating that the mixing of Ce(OH)3 with UO2 is highly favorable. [ABSTRACT FROM AUTHOR]

Pinus sylvestris trees are known to efficiently defend themselves against eggs of the herbivorous sawfly Diprion pini. Their direct defense against eggs is primable by prior exposure to the sex pheromones of this species and their indirect defense involves attraction of egg parasitoids by egg-induced pine needle odor. But it is unknown whether exposure of pine to D. pini sex pheromones also affects pine indirect defense against sawfly eggs. In this study, we investigated the influence of exposure of P. sylvestris trees to the sex pheromones of D. pini on indirect defense mediated by egg parasitoids. Behavioral assays with Closterocerus ruforum, a key parasitoid of sawfly eggs, revealed no significant attraction to odor from egg-free pines pre-exposed to pheromones. Chemical analyses of odor from egg-free pines showed no pheromone-induced change in the emission rates of the known key terpenoids promoting parasitoid attraction. Further comparative analyses of odor from egg-laden pines pre-exposed to the sex pheromones and of odor from egg-laden pines unexposed to pheromones neither revealed significant differences in the emission rates of terpenoids relevant for parasitoid attraction. The results suggest that a pheromone-induced or pheromone-primed, egg-induced pine indirect defense seems to be redundant in addition to the known pheromone-primable pine direct defense against the eggs and the known egg-inducible indirect defense. [ABSTRACT FROM AUTHOR]

Background The formation of charge-transfer complexes (CTCs) of iodine with five chemotherapeutic drugs used for the treatment of different types of cancer has not been investigated. These drugs are olaparib, seliciclib, vandetanib, dasatinib, and tozasertib. Additionally, these drugs need an appropriate general spectrophotometric assay for their analysis in the dosage forms regardless of the differences in their chemical structures. Objective The aim of this study was the development of a novel microwell spectrophotometric assay (MW-SPA) for one-step determination of these drugs via their interactions with iodine, which resulted in instantaneous production of bright lemon-yellow CTCs. Methods A spectrophotometric study of the CTCs was conducted, and all CTCs were characterized. Site(s) of interaction on each drug were assigned, and the MW-SPA was developed and applied to the analysis of dosage forms. Results The findings confirmed that the reactions proceeded via CTC formation. Beer's law was obeyed over a general concentration range of 1–6 µg/mL. The LODs and LOQs were in the ranges of 0.5–2.1 and 1.5–6.4 µg/mL, respectively. The proposed MW-SPA demonstrated excellent precisions as the relative standard deviations were < 2.24 and 2.23% for the intra- and inter-assay precision, respectively. Recovery studies demonstrated the accuracy of MW-SPA. Successful determination of all drugs in bulk and tablet forms was achieved using the MW-SPA. The environmental sustainability of the proposed methodology was determined, providing evidence of the assay's alignment with the basis of green analytical chemistry. The high throughput of the assay was documented. Conclusion In contrast to other existing methods, the MW-SPA described herein was valid for analyzing all drugs at the same wavelength. Highlights The assay is useful for routine analysis of drugs in their formulations in QC laboratories. [ABSTRACT FROM AUTHOR]

During the COVID-19 process, determination-based analytical chemistry studies have had a major place at every stage. Many analytical techniques have been used in both diagnostic studies and drug analysis. Among these, electrochemical sensors are frequently preferred due to their high sensitivity, selectivity, short analysis time, reliability, ease of sample preparation, and low use of organic solvents. For the determination of drugs used in the SARS-CoV-2, such as favipiravir, molnupiravir, ribavirin, etc., electrochemical (nano)sensors are widely used in both pharmaceutical and biological samples. Diagnosis is the most critical step in the management of the disease, and electrochemical sensor tools are widely preferred for this purpose. Diagnostic electrochemical sensor tools can be biosensor-, nano biosensor-, or MIP-based sensors and utilize a wide variety of analytes such as viral proteins, viral RNA, antibodies, etc. This review overviews the sensor applications in SARS-CoV-2 in terms of diagnosis and determination of drugs by evaluating the most recent studies in the literature. In this way, it is aimed to compile the developments so far by shedding light on the most recent studies and giving ideas to researchers for future studies. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) is a powerful tool and an up-to-date method of analytical chemistry due to its high sensitivity and fingerprint recognition capabilities. Nowadays SERS due to its label-free detection capabilities is being actively developed in medical fields, for example in the analysis of biologically important substances in different matrixes, for potential on-site detection of toxic substances, food safety, and so on. To get the SERS signal, it is necessary the presence of plasmonic nanostructures in the SERS substrates. Electrospun nanofibers have been an attractive alternative to SERS-platforms due to the diversity of advantages, including ease of preparation, structure flexibility, and others. In this review, we summarized the methods of plasmonic nanostructures incorporating substrate based on electrospun nanofibers. Also, the analytical application of SERS-active electrospun nanofibers with embedded nanostructures focused on biologically significant molecules is observed in detail. Finally, the future outlook in the application of these substrates in bioanalysis as the most promising area in analytical chemistry is presented. [ABSTRACT FROM AUTHOR]

The reactivity of Bin-clusters (n = 2 to 30) with O2 is found to display even-odd alternations. The open-shell even-sized Bin-clusters are more reactive than the closed-shell odd-sized clusters, except Bi18-, which exhibits no observable reactivity toward O2. We have investigated the structure and bonding of Bi18- to understand its remarkable resistance to oxidation. We find that the most stable structure of Bi18- consists of two Bi8 cages linked by a Bi2 dimer, where each atom is bonded to three neighboring atoms. Chemical bonding analyses reveal that each Bi uses its three 6p electrons to form three covalent bonds with its neighbors, resulting in a Bi18- cluster without any dangling bonds. We find that the robust Bi18 framework along with the totally delocalized unpaired electron is responsible for the surprising inertness of Bi18- toward O2. The Bi18 framework is similar to that in Hittorf's phosphorus, suggesting the possibility to create bismuth nanoclusters with interesting structures and properties. [ABSTRACT FROM AUTHOR]

Rhenium (Re) and its isotopes offer valuable information for understanding various geological processes throughout Earth's history. However, Re isotope analysis remains quite challenging owing to its ultra-trace concentration in geological materials. Previous studies have developed column chemistry and analytical methods for Re isotope analysis, but issues such as tedious pretreatment and incomplete Re recovery still exist. Herein, we present a novel procedure integrating preconcentration and fast column chemistry for Re isotope analysis. Utilizing Na2S solution and activated carbon powder under acidified conditions, we achieved the quantitative recovery of Re from aqueous solutions via filtration while removing most matrices. Standard addition to diverse matrix solutions yielded complete Re recovery (99.6 ± 6.7%, n = 10, 2SD) and precise isotopic compositions (δ187Re = −0.49 ± 0.04‰, n = 10, 2SD), as determined using multi-collector inductively coupled plasma–mass spectrometry. Our method was applied to seawater (7.1 pg g−1 for Re) and solid reference materials (∼0.5–75 ng g−1 for Re), which resulted in stable and high recovery with isotopic results consistent with published data. Our method exhibits efficient matrix removal with stable and essentially quantitative Re recovery, which paves the way for wide applications of Re isotopes in the earth and planetary sciences. [ABSTRACT FROM AUTHOR]

Sustainable catalyst synthesis offers a fundamental development via utilizing plants reducing the dependency on synthetic chemicals and minimizing environmental impact. This study presents a sustainable approach to catalysis through the synthesis of MnO2 using oak bark as a precursor. The catalyst synthesis was characterized using various analytical techniques including Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM–EDX), and High-Performance Liquid Chromatography (HPLC). FT-IR analysis confirmed the chemical structure and functional groups peak observed at 1709 cm−1 is indicative of the stretching vibration of conjugated alkenes' C–C bonds. XRD revealed the crystalline nature and phase purity, confirming the formation of MnO2. HPLC analysis demonstrated the catalytic activity of MnO2 catalyst organic transformations derived from oak bark includes polyphenolic compounds such as gallic acid (RT 9.2 min; C7H6O5), condensed tannins like proanthocyanidin (RT 21.7 min; C31H28O12), quercetin derivatives such as quercetin-3-O-glucoside (RT 32.2 min; C21H20O12), and flavonoids such as kaempferol (RT 35.3 min; C15H10O6). This study emphasizes the feasibility and effectiveness of using natural sources like oak bark for synthesizing eco-friendly catalysis with promising applications in green chemistry. [ABSTRACT FROM AUTHOR]

Manouri, a protected designation of origin (PDO) cheese, is one of the most popular whey cheeses produced in Greece. The objective of the current study was to investigate if there are differences between artisanal and industrial Manouri cheeses regarding microbiological quality, volatile organic compounds (VOCs) profile and other quality parameters (colour, texture), sensory attributes and spectral characteristics detected by Fourier transform infrared spectroscopy (FT-IR) that may discriminate the samples. Differences were detected in the population of the dominant microbial groups, especially for lactic acid bacteria (LAB), Enterobacteriaceae and yeast counts. No discrimination was attained from the physicochemical analyses, except for the pH values. A total of 50 VOCs were identified, including ketones, lactones, free fatty acids, aldehydes, esters, alcohols and hydrocarbons. Sensory evaluation was carried out using a quantitative descriptive analysis (QDA) panel and a consumer panel. Consumers showed a preference for the artisanal Manouri, and the QDA panel revealed significant differences in 11 out of the 17 sensory attributes. Colour and texture analyses were also performed and showed specific differences in yellowness, as well as in fracturability and hardness. FT-IR spectral analysis demonstrated potential discrimination related to the phospholipid content and profile of artisanal and industrial Manouri. [ABSTRACT FROM AUTHOR]

Gallstone formation is one of the most severe human diseases, with regional differences in gallstone composition worldwide. The formation of gallstones inside the gallbladder is a complex process and is still under debate despite advances in instrumentation. This study was an in‐depth analysis of the chemical, structural, and elemental composition of cholesterol and pigment‐type gallstones using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM–EDS). Thermal gravimetric and differential scanning calorimetry (TG‐DSC) analysis was also carried out on gallstones to predict their thermal behavior. FTIR spectroscopy was employed to distinguish the cholesterol and pigment gallstones. Using SEM, we performed the morphological studies of gallstone and EDS were carried out to analyze elemental distribution within the gallstones. Elemental imaging and mapping of the major and minor elements within the cholesterol and black pigment gallstones were carried out, revealing the stone's heterogeneous nature. The level of heavy and toxic elements was found to be higher in pigment stones than in cholesterol gallstones. The results obtained from TG‐DSC are well correlated and supported by the results from FTIR spectroscopy. [ABSTRACT FROM AUTHOR]